A word of warning about brakes

[the Nefyn cat]

Like it says above, just a shortish one. As I've mentioned in other posts, I've got the back axle out of mine to change various bushes, and have fitted braided flexi hoses having had MOT advisories on the old ones being deteriorated. Decided to strip the calipers and rebuild with new seals and a coat or two of paint, and was surprised to see how badly rotted the pistons are, not measured them but there's a good 2mm missing on one side of the piston compared to the other. Will try to get a decent picture or two later, bit gloomy here today. Didn't have any problem with the brakes, but would rather things were right when it comes to brakes.

 

[Lee]

Bare in mind this corrosion is on the other side of the seal so not a huge issue. Long as the corrosion is not under the rubber seal all should be well. I would be more worried about the brake lines themselves as one burst on me working on Windys car.

 

[the Nefyn cat]

Not so much worried about the corrosion as such, more concerned about the piston pushing the pads at an angle, if you see what I mean. Should be a couple of pictures hereabouts, may serve to explain a bit better.


Not the best pictures ever.

 

[Brian4]

Hi @the Nefyn cat agree with you regarding the corrosion because as soon as you change the pads the corrosion becomes an issue as the pistons will start to stick and especially as soon as the plating starts to deteriorate below where the dust cover groove is as this section is inside the cylinder when the new pads are fitted. Also yours look to be pushing the pads/piston at an angle as you said.

These were my fronts which had stuck in place. new and old

 

[the Nefyn cat]

New pistons only £18 or so from Bigg Red, not exactly over the top. Did think about having them lathed down flat again, but would probably cost nearly as much and would lose too much off the pistons. Just something else to look out for if anyone else is changing pads/discs in the future, didn't notice when I changed all mine back in April.